diff --git a/mod/url/lang/en/url.php b/mod/url/lang/en/url.php
index be6867d4743..4498394bc59 100644
--- a/mod/url/lang/en/url.php
+++ b/mod/url/lang/en/url.php
@@ -45,6 +45,7 @@ $string['displayselectexplain'] = 'Choose display type, unfortunately not all ty
 $string['externalurl'] = 'External URL';
 $string['framesize'] = 'Frame height';
 $string['chooseavariable'] = 'Choose a variable...';
+$string['invalidurl'] = 'Entered URL is invalid';
 $string['modulename'] = 'URL';
 $string['modulenameplural'] = 'URLs';
 $string['neverseen'] = 'Never seen';
diff --git a/mod/url/mod_form.php b/mod/url/mod_form.php
index da6a7209dc7..790b85dc534 100644
--- a/mod/url/mod_form.php
+++ b/mod/url/mod_form.php
@@ -50,6 +50,7 @@ class mod_url_mod_form extends moodleform_mod {
         //-------------------------------------------------------
         $mform->addElement('header', 'content', get_string('contentheader', 'url'));
         $mform->addElement('url', 'externalurl', get_string('externalurl', 'url'), array('size'=>'60'), array('usefilepicker'=>true));
+        $mform->addRule('externalurl', null, 'required', null, 'client');
         //-------------------------------------------------------
         $mform->addElement('header', 'optionssection', get_string('optionsheader', 'url'));
 
@@ -165,4 +166,14 @@ class mod_url_mod_form extends moodleform_mod {
         }
     }
 
+    function validation($data, $files) {
+        $errors = parent::validation($data, $files);
+        //Validating Entered url
+        $data['externalurl'] = clean_param($data['externalurl'], PARAM_URL);
+        if (empty($data['externalurl'])) {
+            $errors['externalurl'] = get_string('invalidurl', 'url');
+        }
+        return $errors;
+    }
+
 }